EF6805R3

EF6805U3 8-BIT MICROCOMPUTER UNIT . . . . . . . . . . . . . . . . . . . . . . HARDWARE FEATURES 32 TTL/CMOS COMPATIBLE I/O LINES 24 BIDIRECTIONAL (8 lines are LED compatible) 8 INPUT-ONLY 3776 BYTES OF USER ROM 112 BYTES OF RAM SELF-CHECK MODE ZERO-CROSSING DETECT/INTERRUPT INTERNAL 8-BIT TIMER WITH 7-BIT SOFTWARE PROGRAMMABLE PRESCALER AND CLOCK SOURCE 5V SINGLE SUPPLY SOFTWARE FEATURES 10 POWERFUL ADDRESSING MODES BYTE EFFICIENT INSTRUCTION SET WITH TRUE BIT MANIPULATION, BIT TEST, AND BRANCH INSTRUCTIONS SINGLE INSTRUCTION MEMORY EXAMINE/CHANGE POWERFUL INDEXED ADDRESSING FOR TABLES FULL SET OF CONDITIONAL BRANCHES MEMORY USABLE AS REGISTER/FLAGS COMPLETE DEVELOPMENT SYSTEM SUPPORT ON INICE USER SELECTABLE OPTIONS 8 BIDIRECTIONAL I/O LINES WITH TTL OR TTL/CMOS INTERFACE OPTION 8 BIDIRECTIONAL I/O LINES WITH TTL OR OPEN-DRAIN INTERFACE OPTION CRYSTAL OR LOW-COST RESISTOR OSCILLATOR OPTION LOW VOLTAGE INHIBIT OPTION VECTORED INTERRUPTS : TIMER, SOFTWARE, AND EXTERNAL USER CALLABLE SELF-CHECK SUBROUTINES DESCRIPTION The EF6805U3 Microcomputer Unit (MCU) is a member of the 6805 Family of low-cost single-chip Microcomputers. The 8-bit microcomputer contains a CPU, on-chip CLOCK, ROM, RAM, I/O, and TIMER. It is designed for the user who needs an economical microcomputer with the proven capabilities of the 6800-based instruction set. A comparison of the key features of several members of the 6805 Family of Microcomputers is shown at the end of this data sheet. The following ar...